Karaköy (Turkish pronunciation: [kaˈɾɐcøj]), the modern name for the old Galata, is a commercial quarter in the Beyoğlu district of Istanbul, Turkey, located at the northern part of the Golden Horn mouth on the European side of Bosphorus.

The commercial quarter, which was originally the meeting place for banks and insurance companies in the 19th century, is today also home to mechanical, electrical, plumbing and electronic parts suppliers.

After the re-conquest of the city from the Latin State in 1261, the Byzantine emperor granted Genoese merchants permission to settle and do business here as part of a defense pact.

Karaköy experienced a second wave of Christian arrivals when British, French and Italian forces of the Allies came to Istanbul to fight in the Crimean War (1854–1856).

The lack of piers made the unloading of troops and military equipment difficult so in 1879, a French company obtained a concession to build a new quay in Karaköy, which was completed in 1895.

Şehir Hatları ferries leave for Kadıköy and Üsküdar on the Asian shore of the Bosphorus, as well as for terminals along the Golden Horn as far as Eyüp.

Cruise ships from Mediterranean ports such as Piraeus in Greece, Dubrovnik in Croatia, Civitavecchia (Rome) and Venice in Italy berth at the nearby Galataport complex.

All kinds of hardware, tools, plumbing items and spare parts are for sale in Tersane Street in Perşembe Pazarı (literally Thursday Market).